The evaporative coil carries coolant from the compressor to the heat-exchanging condenser so that coolant can ultimately be condensed to a liquid and returned to the evaporator assembly in a refrigeration system. Because of compression, the coolant is actually very hot and hot coolant flowing through the evaporative coil is normally used to assist in the evaporation of any condensed moisture collected in a condensate pan including liquids and condensed water vapour drained from the refrigerated interior of an associated cabinet. Conversely, condensed moisture emerging from an evaporator assembly which collects in the condensate pan can be used to define a pre-cooling stage so as to assist in cooling gaseous coolant in the evaporative coil emerging from the compressor prior to entry into a heat-exchanging condenser.
A problem which arises with such an arrangement is that contact between the evaporative coil and moisture in the condensate pan results in corrosion in the evaporative coil which normally is a bent piece of copper tubing. Copper is a material of choice because it is inexpensive, it is heat conductive, and easy to form and weld.
An object of this invention is to minimize corrosion of the bare copper tubing used as an evaporative coil in a refrigeration system.